[Clayart] firing a bit faster

Ray Bogle rbogle at comcast.net
Mon Sep 6 21:48:24 UTC 2021

Just fired my MFT on Saturday and once again used the Mel inspired "let 
it rip...." concept.  I haven't quite made it to Cone 11 in 5hrs but I 
regularly hit cone 10 in 6hrs and everything perfect by my standards :)

On 9/6/21 9:03 AM, mel jacobson wrote:
> We have fired the big salt kiln here at the farm several times
> this late summer.  It is a huge reminder of what firing a hard brick
> kiln is like.  It is a throw back firing to 1950 and of course
> much earlier.
> It is like the discussion of zinc, there are a great many things to know
> and understand if you are a "do it yourself" artist/potter.
> All kilns were made of hard brick, mostly 9 inches thick before and after ww2.
> There were standards of firing practice that had a great deal more to do with
> how they fired and timing rather than changing how to fire.  The kilns just fired
> in 12 hours. They took 24 hours to cool.  And when that is how they worked, the standard
> for firing was set. It was just.."that is just the way it is."  The teachers told
> us how to do it...it became "law".
> After the first atomic bomb work, smashing atoms, nose cones of rockets, extreme
> heat work and the first use of ceramic melted to fiber, spun into Kaowool
> and the use of saw dust in the brick.."IFB's" did the standard for firing change.
> But the "law was in place".  Long warm up, slow firing, fire to cone 10 just half over.
> Slow cool as long as you can.
> When Nils and I started to "fast fire", as it is called, we were looked at with great suspicion.
> "Can't do that you know."  Warm the kiln overnight, even though you have a perfectly insulated
> kiln.  And of course that warm up destroys the K factor and the insulation. Does not matter, the
> kiln and pots like slow.
> anyway, it seems that a few are starting to understand that well dried, well balanced clay bodies
> with fine sand or grog can be fired much faster than the old law required. It was nothing but a huge
> fuel waster. It is an old rule.....If I fire my 45 cubic inch kiln in 6 hours and another potter
> fires their kiln in 12 hours..."under house rules" who wins the ecology war.  I do.  And I save
> gobs of money.
> The new rules are based on "how does your kiln fire?"   Most potters have no idea because they
> still use the old rules for hard brick firing. Find the magic timing of your kiln.( of course we
> still have people writing code for auto kilns that use 1955 standards of firing practice.)
> "you are firing too fast."  "shut up, leave me alone, don't tell me what to do."
> Just a reminder. Your ifb kiln with good gas pressure, or electric power will serve you well. My pots
> love cone 11, fired in 5 hours. But, I make a clay body and glazes that adore the firing
> system.  You sure cannot take a cone 9, tight, pure white clay and rush the system. It is all
> about the logic of what you are doing. Just more food for thought.
> It is like magic amulets on your kiln...""When you fire with logic, the amulets work well."
> mel
> website: www.melpots.com
> www.melpots.com/CLAYART.HTML

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